Diesel engine fuel



Patented Mar. 1, 1938 Arthur Burwell, Niagara Falls, N. Y., assignor toAlox Corporation, New York, N. Y., a corporation of New York ApplicationOctober 9, 1935, Serial No. 44,269

'2 Claims. (01. 44-9) This invention relates to an improved method oflubricating the fuel injectors of internal com-= bustion -motors of theinjection engine type wherein a liquid fuel is positively injected intothe combustion space.'

The fuels used in Diesel motors are, in general, non-viscous mixtures ofrelatively low-molecular weight hydrocarbons of mineral origin, whichmixtures have substantially no capacity to form a lubricating film whichwould resist rupture at even medium pressures per unit area at normal orelevated temperatures. Such fuels include the hydrocarbonmixtures knownas gasoline, kerosene, fuel oil, and the like.

pression fuel oil is intended to include those fractions of petroleumcommonly sold or used as fuel oils and characterized by havinginsumcient oiliness to prevent wear, e. g., the fraction known as 36-40"Beaum distillate. The fuel, whatever it may be, is positively forced,with or without combustion-supporting gas, e. g., air, into The exthecombustion space throughnthe agency of an injecting pump.

Such pumps or adjustable injection devices associated with injectionengines, normally are so constructed that there is no opportunity fortaking up wear or for using stufllngboxes or other packing means:instead, the surfaces in-- tended to have relative movement are veryfinely ground and nicely fitted to eachother by hand, whereby to avoidleakage of iiuidiuel. Because of the known wear of such inuse, they havebeen fabricated from hardened steels, nitrided steels, and otherwear-resisting alloys; these Pumps or injectors represent, in somecases, a

large part of the total cost of the power-producing device. In spite ofthese precautions. wear- The liquid fuels commonly used in this type ofmotor may and frequently do contribute another engineering problem, thefgumming or impaction of the top rings of the motor pistons. Thisgum'ming apparently is occasioned by the existence in such fuels ofunsaturated compounds -which,'upon storage of the fuels, accrue to amaterial extent. Addition to the liquid fuel of an improperoiliness-conferring material may aggravate gumming. It is another object'01- the present invention to provide the liquid fuel with a non-gummingoiliness agent. i

It is a fact that oiliness in fuels of the hereinbefbre described typesmay be provided by dissolving in the same a material which will bringabout segregation of lubricating molecules at the metal surfaces: fatoils (vegetable or animal) appear, in general, to produce somelubricating effect when dissolved in the fuel. However, an oilinessagent to be usable in this relation must possess other characteristicsbesides alubricating eifectz'it must not have a gumming effect; it mustnot etch metal or otherwise deteriorate metal surfaces; and should, tobe commercially usable, be so inexpensive as not materially to increasethe cost of the fuel so treated.

It has been found that the above criteria are met, and the above andother objects of invention are realized, by addition to the mixture ofnormally liquid petroleum hydrocarbons constituting the injection enginefuel, prior to its admission into the fuel pump or injector, of arelatively very small amount of an oiliness agent obtained from thereaction product of the controlled liquid-phase partial oxidation ofamixture of saturated aliphatic hydrocarbons of mineral origin, such asthe mixture of hydrocarbons known as paraflin wax, the mixture known as"crude scale wax", the mixture known as amorphous wax" or Sharples'wax", various petroleum distillates (such, for instance, as the 36-40fuel oil above described), or a mixture of two or more of the abovestarting mate-' rials. Such oiliness agents per se, and methods wherebythey may be obtained from mineral hydrocarbons, are described in Patent-'No. 1,863,004 to Arthurxw. Burwell, wherein patentee disclosed andclaimed the concept of. dissolving such oiliness agents in lubricatingoils whereby to produce improved lubricating oil compositions. Saidoiliness agents are oil-soluble compositions consisting essentially ofmixtures of a. plurality of relatively high molecular weight,saturated,- aliphatic, oxygen-containing compounds, whichoxygen-containing compounds may or may. not contain free acids Thus, theagent may be.

. 1. The residue obtained by removingunoxidmd hydrocarbons from thewhole oxidation reaption 2. The residue 1. above, modifiedbyester-incation of the free acids content thereof.

3. The free acids content of 1. above.

- oiliness agent, in admixture, alcohols, ketones,

alcohol-ketones, lactones and esters produced as aforesaid by thecontrolled, liquid phase, partial oxidation of mixtures of saturatedaliphatic hydrocarbons of mineral origin. As is set out inthe aforesaidPatent No. 1,863,004, said alcohols, ketones, alcohol-ketones, lactonesand esters are all of relatively high molecular weight, 1. e., con--sist of aliphatic chains of more,than 5 carbon atoms each.

I have found that by the incorporation of relatively very small amounts,e. g., from ,12% to 1% or more, by weight, but notin excess of 4% byweight. of these oil-soluble oiliness agents. as such, into gasoline orother light petroleum fuel such as 3fi'-40 fuel oil the resulting fuelcomposition effectively lubrtcates the pumps or injectors aforesaid,whereby wear therein is greatly retarded and the eiflciency of thedevice is maintained. In some instances as little as 54% of: theoiliness agent is sumcient. It has been found that the presence of theseagents prevents gumming or impaction of the piston rings; that theagents do not etch or otherwise harm the metal surfaces which theylubricate; and that they may be added, to the fuel in effective amountswithguzl materially increasing the total cost of the The fuelcompositions of the present invention are simply prepared by dissolvingthe predetermined small amount of the agent in the fuel to be moved bythe injection engine pump or injector: this may be efiected, en masse,by admixing the agent with a body of the fuel prior to use. It may alsobe effected by adding the agent to the stream of fuel just before or asthe latter enters the pump or injector.

Numerous tests, scientifically carried out, have negligible lubricity,e. g., gasoline, kerosene, 36-40 fuel oil, or the like, and a relativelyvery small amount e. g., from about to 1% or more, of the agentaforesaid, in the absence of any other oiliness agent, has sufllcientlubricity in and of itself to reduce to a minimum the wear of movingparts of the pumps or injectors used in positively forcing liquid fuelinto the combustion space of the injection engine. This is remarkableinthat it heretofore had been believed that to confer lubricity upon aliquid fuel of the nature of gasoline, kerosene, 36-40 fuel oil or thelike it was necessary to incorporate in the latter a lubricating oilwith or without added oiliness agent. The latter concept is describedand claimed in my copending application Serial No. 691,242, filedSeptember 27, 1933, for Top cylinder lubricants".

I claim:

' 1. An injection engine fuel consisting essentially of from about 99.5%to about 96.0% by weight of a' mixture of ,normally liquid non viscousrelatively low molecular weight petroleum hydrocarbons of too lowlubricity to prevent wear of the injection engine injecting apparatusand from about 0.5% to not more than about 4.0%

by weight of an oiliness agent soluble in the petroleum hydrocarbonmixture and consisting essentially of a mixture of non-acidic saturatedpartially oxidized aliphatic chain hydrocarbons of more than 5 carbonatoms each including alcohols, ketones, alcohol-ketones, lactones andesters.

2. An' injection engine fuel consisting essentially of a solution offrom about 0.5% to about 1% by weight of an oil-soluble. oiliness agentcon-. sistlng essentially of a mixture of non-acidio saturated partiallyoxidized aliphatic chain hydrocluding alcohols. ketones,alcohol-ketones, lactones and esters produced by the liquid phasepartial oxidation of a petroleum hydrocarbon. mixture, in from about99.5% -to about 99.0% by weight of a liquid fuel of the group consistingof gasoline, kerosene and fuel oil.

' ARTHUR W. "BURWELL.

